To make the Cajun seasoning, in a small container with a tight-fitting lid, stir together the garlic, onion, sweet paprika, smoked paprika, cayenne, oregano, thyme, salt and black pepper.,Cover and shake vigorously to mix.,Use immediately, or store in a cool, dark place for up to 1 month.,You will need 2 Tbs.,______,If using wooden skewers, soak 6 to 12 skewers in water for at least 30 minutes.,Bring a large saucepan three-fourths full of water to a boil over high heat.,Add the potatoes and corn and cook for 5 minutes.,Drain and immerse in ice water to stop the cooking.,Using kitchen shears, snip open the shell along the length of the back of each shrimp.,Then, using the tip of a small knife, cut a shallow groove along the length of the vein and lift it out.,Thread the shrimp, sausages and vegetables onto the skewers, dividing them evenly.,Place the skewers on a tray or platter and sprinkle them evenly with the Cajun seasoning.,Let stand while you prepare the fire.,Prepare a medium fire in a grill.,Brush and oil the grill grate.,Place the skewers on the grill directly over the heat.,Cook, turning once with tongs, until the shrimp turn creamy white and the potatoes are tender, 3 to 5 minutes per side.,Slide the shrimp, sausages and vegetables off the skewers onto a platter and serve immediately.